Composition useful as an antioxidant for fats and oils



Patented Aug. 19, 1952 COMPOSITION USEFUL AS AN AN'rIoXmANr ron FATS AND or s r 2,607,746 E OF C -.9;

James E. Magoifin, Kingsport, rem, 'assignor to Eastman Kodak Company, Rochester, N. Y., a

corporation of New Jersey 7 No Drawing. Application July 2 6, 1349, 2'

Serial No. 106,951 8 Claims. (01. 252-404) This invention relates to a composition useful as an antioxidant for fats and oils. This application is acontinuation-in-part of my application Serial No. 81,842, filed March 16, 1949, now abandoned. p

It has long been known that phenols, such as hydroquinone, guaiacol, eugenol, gallic acid and its esters, e. g. tannin (penta-[m-digalloyllglucose), etc. are useful as antioxidants for fats and oils (Moureu et a1., Compt. rend. 174, 258 (1922)). It is also known that thephenolic compounds such as the alkylated hydroxyphenyl ethers (for example, alkylated hydroxyanisoles, etc.) can be used as antioxidants for fats and oils. It is further known that the antioxidant action of such phenolic antioxidants can be synergized with acids, e. g citric acid, orthophosphoric acid,

tartaric acid, etc. While these phenolic compounds, as well as their synergistic combinations with acids, such as citricacid, etc. have been found to be adequately effective in retarding oxidative rancidity during storage of fats and oils, they are subject to the disability in many instances of being only slightly soluble in the fatty materials to which they are added. In processing such'fats and oils, a considerable percentage of the effective amounts of the antioxidants are frequently lost due to this lack of sufiicient solubility; Y 1 g Lhave now found that the dispersion of mixtures ofcertain of these antioxidants in fats and oils can be materially improved if a concentrate of these antioxidants in propylene glycol is employed. This concentrate has the advantage of materially increasing the solubility or dispersability of mixtures of certain of the antioxidants in the fatty material to be stabilized,

thus enabling one to secure uniformly dispersed mainder being propylene glycol'plus at least one 4 alk-ylated hydroxyphenyl ether, or propyleneigly-' col plus at least one alkylated hydroxyphenyl ether plus at least one synergizing acid. 7 iv o The total weight of the alkylated hydroxyphenyl ether is advantageously from 10 to 50 per cent of the total weight of the concentrate. Where at least one synergizing acid is employed, the total weight of the synergizing acid is advantageously from 3 to 10 per cent of the total weight of the concentrate. In no case should the weight 2 H h of propylene glycol be lessthan from 20 to per cent of the total weight oftheconcentrate.

Advantageously the total weight of the alkylated "hydroxyphenyl ether employed is fromlJO to 5 times-the total weight of the gallicesteri Advantageously the total weight of-the 'syne'r' gizing acid is from 0.2 to 1 times the total weight of the gallic ester. 7 I g The gallic esters which I employ in practicing my invention can be represented by the follow' ing general formula:

UOOR

wherein R represents an alkyl group containing from 1 to 5 carbon atoms, e. g. methyl, ethyl, npropyl, isopropyl, n-butyl, isobutyl, n-amyl, etc. Typical examples are: methyl gallate, ethyl gallate, n-propyl gallate, isopropyl gallate, n-butyl gallate, isobutyl gallate, n-amyl gallate, etc.

The alkylated hydroxyphenyl ethers which I employ in practicing my invention can be represented by the following general formula:

wherein R1 represents an alkyl group containing; from 1 to 2 carbon atoms, and R2 represents a tertiary alkyl group containing from 4 to 5- carbon atoms. Typical examples are 2-tert. butyl: -hydroxyanisole, 3-tert. butyll-hydroxyani sole, 2 -tert. butyl-l-hydroxyphenetole, 3-tert. butyl 4 hydroxyphenetole, 3-tert. amyl--hydroxyanisdle, ,3 tert. amyl--hydroxyphenetole, etc/no Among the synergizing acids-which I" employ are: citric acid, orthophosphor ic acid, tartaric;- acid, ascorbic acid, etc. V H Efiicacious concentrates are set forth in the. following examples: 7 i

EzcampleI V 1f 1 IPartsby weight nl-Propyl gallate r Citric ]aCid- '.Y..'. V V The above concentrate is-ofs'uch composition that one pound is sufficient to stabilize oneton of lard. I Such a concentrate is a homogeneous system even attemperatures as low as 20 (2.:

It is, therefore, capable of being manufactured and handled in ordinary channels of commerce without separation of the added components. Propylene glycol is satisfactory for incorporation in edible products in concentrations much greater than result from use of this mixture. In contrast to propylene glycol, a'material such as glycerin will not function in a satisfactory manner.

In contrast to fats stabilized against oxidative rancidity with mixtures of the aforesaid antioxidants without the use of propylene glycol as a dispersing medium, fats stabilized with the concentrate set forth in the above example contained the antioxidant dispersed throughout the entire body of; thevfat, thus enabling the fatty material tube-stored for longerperiods of time, and also tp}be;further processed; (as, for example, by cooking; etc.) without serious depletion of the antioxidant, to, giveproducts which are also. stable to the influencesof oxidative rancidity, n

In;- the above; exanflple, the n -p ropyl gallate be replaced with an equal weight f methyl.

eal ia esa ic n) eth l a l te, iscp ny g l a e, n-butyl gallate,n -amylgallate, etc. Likewisethe citric acid can be replaced with an equal Weight of ascorbic acid, orthophosphoric acid or tartaric acid.

The butylated hydroxyanisole of the above example is a mixture of equal parts by weight of:

3rtert. butyl-d-hydroxyanisol'e and : GE's I QTCHHS,

CHs

2-tert. butyl-4-hydroxyanisole Instead of this mixture an equal weight of either 3-tert. butyl-4-hydroxyanisole or 2-tert. butyl-4- hydroxyanisole can be employed, or an equal weight of- Z-tert'. butyl--hydroxyphenetole, 3 tert; butyll-hydroxyphenetole, Z-tert. amyl-4- hydroxyanisole, 3-tert; amyl=4 hydroxyanisola 2- tert. amyl l hydroxyphenetoleor 3-tert. amyl-4- hydroxyphenetole can be employed.

' Ex mple 2 Parts-by weight Propylene glycol 30.

Butylated hydroxyanisol'e 41:.2 n-Propyl gallate 20.6. Citric acid 82 Such a concentrate is a homogeneous system, even at temperatures as low as -20 C. 'As in Example.

1, the n-propyl gallate can be replaced with methyl" gallate (-gallicin), ethyl gallate, isopropyl gallate-,- n-butyl gallateor n-amyl gallate. I The citric acidcan- -be replaced with -ascorbic acid, orthophosphor-ieacid or----tartaric acid. The butylated hydroxyanisole has thesamemeanme; win Example 1 and: can be replaced with. 3 tent: b ty1- ehydroxyaniso1e; or 2-tert. butyllhydroxyanisole or by Z-tert. butyl-4-hydroxyphenetole, 3-tert. buty1-4 hydrqxyphenetole, 2.

seed oil, sesame oil,,hydrogenated' oils or: shorten.-

tert. amy1-4-hydroxyanisole, 3-tert. amyl-4-hydroxyanisole, 2-tert. amyll-hydroxyphenetole or 3-tert. amyl-4-hydroxyphenetole.

Emmple3 Parts by weight Propylene glycol 70 Butylated hydroxyanisole 20 n-Propyl ga1latel 6 Citric acid 4 droxyanisole or by Z-tert. butyll-hydroxyphenetole, B-tert. butyl-4-hydroxyphenetole, 2ftert; amyl 4 hydroxyanisole, 3-- tert. amyl --4 hy-' droxyanisole, 2 -tert. amyl-4-hydroxyphenetole or 3-tert. amyl-i-hydroxyphenetole.'

My concentrate can be employed to stabilizeall fats and oils, e. g. glycerides. of fatty'acids, such, as lard, tallow, peanut oil, palm oil, cocoa nut oil, cottonseed 0il,-soya bean oil, sunflowering s (especially those of, the dry plastic; type) and fatand oil mixtures.

By the term propylene glycol, I-mean the compound which has the following formula:

HOCHCHz-*O'H- The alkylated hydroxyphenyl ethersv can be; prepared by reacting p.-hydroxy anisole or p-hydroxyphenetole with tert. butyl or tert. amyl alcohol, at a temperature of from 80, tov (3., in the presence of phosphoric, acid as, a: catalyst. The alkylated hydroxyphenyl ethers can also. be p epa by reac n .nydr xy ni le: or n-hy- 'dr yp e t le, w th isobutylene or ,with: isoamylene, in the presence: of; sulfuric acid;

The gallic esters whichI employ in practicing;

my inventionv can begprepared as described by: Hepner and. Zyto, Roczniki Chemji: 12; 100, (1932):.

What I, claim as, my invention; and desire;v to. be securedby Letters .Patentof theUnited States.

l. A concentrate. containing propylene. :glycoly.

at least onev gallic cester' selected from the groupconsisting of those. represented: by the-following general formula:

' 50011 wherein Rxrepresents an alkyl group containing from 1 to; .5 1 carbon atoms,. and; at l'east one alky' lated hydroxyphenylether selectedfrom those. representech by the following general formula: r

wherein R1 represents an alkyl groupcontaining from 1 to-2 carbonatomsrand R/zrrepresents a tertiary alkyl group containing from 4 to 5 car bon atoms, the total weight ofigallic ester being from 3 to 30 percent of the'total'weight of the concentrate, and the total weight of the Valkylated hydroxyphenyl ether being from 10 to 50 percentof the total weight of theconcentrate.

2. A concentrate containing propylene glycol, at least one gallic ester selected;from.the group consisting of those represented by the following general formula: Li- 1 .7

HO OH COOR wherein R represents an alkyl group containing from 1 to 5 carbon atoms, at least one alkylated hydroxyphenyl ether selected from the group represented by'the following general formula:

wherein R1 represents an alkyl group containing from 1 to 2 carbon atoms and R2 represents a tertiary alkyl group containing from 4 to carbon atoms, and at least one synergizing acid selected from the group consisting of citric acid, orthophosphoric acid, tartaric acid and ascorbic acid, the total Weight'of the gallic ester being from 3 to 30 percent by weight of the total weight of the concentrate, the total weight of the alkylated hydroxyphenyl ether being from to 50 percent of the total weight of the concentrate, and the total weight of the synergizing acid being I from 3 to 10 percent of the total weight of the concentrate, the weight of the propylene glycol being from 20 to 80 percent of the total weight of the concentrate.

3. A concentrate containing propylene glycol, at least one gallic ester selected from the group consisting of those represented by the following general formula:

wherein R represents an alkyl group containing from 1 to 5 carbon atoms, at least one alkylated hydroxyphenyl ether selected from the group represented by the following general formula:

wherein R1 represents an alkyl group containing from 1 to 2 carbon atoms and R2 represents a tertiary alkyl group containing from 4 to 5 carbon atoms, and at least one synergizing acid selected from the group consisting of citric acid, orthophosphoric acid, tartaric acid and ascorbic acid, the total weightof the gallic ester being from 3 to 30 percent by weight of the total weight of the concentrate, the total weight of the alkylated hydroxyphenyl ether being from- 10 to 50 percent of the total weight of the concentrate, and the total weight of the synergizing acid being from 3 to 10 percent of the total weightoi the concentrate, the .weight of the propylene; glycol being from 20'to80 percent of the tot'alwei'ght of the concentrate, the total weight of the 'alkylated hydroxyphenyl ether being from 1.0 to 5 times the total weight of the gallic ester an the total weight of the synergizing acid being from 0.2 to 1 times the total Weight of the gallic ester. 4. A concentrate containing propylene glycol, n-propyl gallate, a mixture of 2-tert. butyl-4-hydroxyanisole and 3-tert. butyl-e-hydroxyanisole and citric acid, the weight of the n-propyl gallate being from 3 to 30 percent of the total weight of the concentrate, the weight of the mixture of 2-tert. butyl-4-hydroxyanisole and 3- tert. butyl-4-hydroxyanisole being from 10 to 50 percent of the total weight of the concentrate, the weight of the citric acid being from 3 to 10 percent of the total weight of the concentrate, the weight of the propylene glycol being from 20 to percent of the total weight of the concentrate. 5. A concentrate containing propylene glycol, n-propyl gallate, a mixture of 2-tert. butyl-lhydroxyanisole and 3-tert. butyl-4-hydroxyanisole and citric acid, the weight of the n-propyl gallate being from 3 to 30 percent of the total weight of the concentrate, the weight of the mixture of 2-tert. butyl-4-hydroxyanisole and 3-tert. butyl-l-hydroxanisole being from 10 to 50 percent of the total weight of the concentrate, the weight of the citric acid being from 3 to 10 percent of the total weight of the concentrate, the weight of the propylene glycol being from 20 to 80 percent of the total weight of the concentrate, the total weight of the mixture of the 2-tert. butyl-e-hydroxyanisole and 3-tert. butyl-4-hydroxyanisole being from 1.0 to 5 times the weight of the n-propyl gallate and the weight of the citric acid being from 0.2 to 1 times the weight of the n-propyl allate and the weight of the citric acid being from 0.2 to 1 times the weight of the n-propyl gallate.

6. A concentrate having the following composition:

Parts by weight Propylene glycol 60 Mixture of 2-tert. butyl-4-hydroxyanisole and 3-tert. butyl-i-hydroxyanisole 23.5 n-Propyl gallate 11.8 Citric acid 4.7

7. A concentrate having the following composition:

Parts by weight 8. A concentrate having the following composition:

Parts by weight Propylene glycol 70 Mixture of Z-tert. butyl-i-hydroxyanisole and B-tert. buty1-4-hydroxyanisole 20 n-Propyl gallate 6 Citric acide 4 JAMES E. MAGOFFIN. (References on following page) I 7 I 'REEER NCES: 015m)- iihi filming referencesar of 118.com in the. file of this} potent;

' UNITED, STATES PATENTS I Number Name; Date,

OTHER REFERENCES Boehm e1: a1: A Study of'the Inhibiting Acmom of? 'Propyl Gall'ate (Normal Propyl- Trih-ydroxmBenzoate); and Certain Other Trihydric Phenolsu onstheuAutoxidation of. Animal andivegetable Oi1s,v-Qu:=mrt.v Journal of Pharm, vol. 16 (19437), pgs. 232-243. I

Gregory Uses and Applications oi Chemicals andRelated Materia1s,."vo1-. II, p. 27.6., Reinhold Pub...C0., N. Y'. CL, N. Y; (1944').

Riemenschneider; Oxidative Banc'idity' and the.- ;Use of Antioxidants, Trans.. Assoc.

tin No. 2, Apr. 1948, The American. Meat Institute Foundation, pgs. 1-7. 

2. A CONCENTRATE CONTAINING PROPYLENE GLYCOL, AT LEAST ONE GALLIC ESTER SELECTED FROM THE GROUP CONSISTING OF THOSE REPRESENTED BY THE FOLLOWING GENERAL FORMULA: 